JP2000019514A - Liquid crystal illumination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To brightly illuminate a liquid crystal display surface and to enhance visibility even under the environment where a light quantity is small while taking advantage of the characteristics of a reflection type liquid crystal display panel of a small size and lightness in weight. SOLUTION: A casing 1 having the reflection type liquid crystal display panel 2 is internally provided with an illumination mechanism housing space 4 in which a light source 5, a second reflection plate 7 and a first reflection plate 8 are housed. The first reflection plate 8 is selectively positioned to a housing position where the reflection plate is housed in the illumination mechanism housing space 4 and an illumination position B2 where the reflection plate is popped up and the reflection type liquid crystal display panel 2 is illuminated. The reflection type liquid crystal display panel 2 may be used in a compact state that the first reflection plate 8 exists in the housing position under the bright environment where the light quantity is large. The first reflection plate 8 is popped up and the reflection type liquid crystal display panel 2 is brightly illuminated under the environment where the light quantity is small.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a liquid crystal lighting device for illuminating a reflection type liquid crystal display panel.

[0002]

2. Description of the Related Art In recent years, displays used in personal computers and the like have been small in size and have low power consumption.
In addition, liquid crystal display panels have been rapidly spreading because of their excellent characteristics of generating less harmful electromagnetic waves. In particular, in a portable personal computer called a mobile computer, it is essential to attach a liquid crystal display panel.

However, since the liquid crystal display panel alone has insufficient brightness, an illumination device for illuminating the liquid crystal display surface is required. Conventionally, as such a lighting device, a lighting device as illustrated in FIG. 4 has been widely used. In this lighting device, a lamp 102 is arranged on a side end surface of a light guide plate 101, irradiation light from the lamp 102 is incident on the light guide plate 101, and light emitted from the surface of the light guide plate 101 illuminates a liquid crystal display panel (not shown). It is of such a structure. Light emitted from the surface of the light guide plate 101 includes light directly emitted from the surface of the light guide plate 101 and light emitted from the back surface of the light guide plate 101 and reflected by the reflection plate 103, and is again incident on the light guide plate 101. And light emitted from the surface of the light guide plate 101.

In recent years, portable personal computers called mobile computers have been rapidly reduced in size and weight. Therefore, the light guide plate 10 as illustrated in FIG.
In the lighting device for a liquid crystal display panel using the light guide plate 1, the light guide plate 10
The use of a lighting device having such a structure in a portable personal computer is not desirable because 1 impairs the size and weight of the liquid crystal display device.

On the other hand, conventionally, a liquid crystal display device having a reflection surface of its own, called a reflection type liquid crystal display panel, has been developed and put to practical use. FIG. 5 is a schematic diagram showing the principle of such a reflective liquid crystal display panel. As shown in FIG. 5, the reflection type liquid crystal display panel has an ITO film (transparent conductive film) for preventing noise on a surface of a lower glass substrate on which a polarizing plate and a diffuse reflection plate are sequentially formed on the lower surface. It has a structure in which a sandwiched liquid crystal material is laminated, a color filter is laminated thereon, an upper glass substrate is laminated thereon, and a polarizing plate is further laminated thereon. In the reflection type liquid crystal display panel having such a structure, external light incident from the surface reflects the diffuse reflection plate to illuminate the liquid crystal display surface brightly. At this time, the liquid crystal display surface is illuminated uniformly and with high brightness by the light diffusion action of the diffusion plate.

[0006]

In a reflection type liquid crystal display panel as exemplified in FIG. 5, the illuminating action of the liquid crystal display surface exclusively depends on external light. For this reason, there is a problem that the liquid crystal display surface has a sufficient illumination effect on the liquid crystal display surface in a dark environment with a small amount of light, while exhibiting a sufficient illumination effect on the liquid crystal display surface outdoors or indoors with strong light.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid crystal illuminating device capable of brightly illuminating a liquid crystal display surface even in an environment with a small amount of light and improving visibility while making use of the characteristics of a small and light reflective liquid crystal display panel. It is.

Another object of the present invention is to realize further miniaturization of the device.

[0009]

The invention of a liquid crystal lighting device according to the first aspect of the present invention is directed to a flat casing-shaped casing; a reflective liquid crystal display panel attached to one display surface of the casing; A lighting mechanism housing space provided on a side; a light source housed in the lighting mechanism housing space; a light source protruding from a display surface of the casing from the lighting mechanism housing space; And a displacement mechanism for displacing the reflection plate between its storage position and the illumination position.

Here, as the "light source", for example, a cold cathode fluorescent lamp is used.

According to the first aspect of the invention, in a bright environment with a large amount of light, the liquid crystal lighting device is used in a compact state with the reflection plate stored in the storage position. On the other hand, in a dark environment where the amount of light is small, the reflecting plate is displaced to the illumination position by the displacement mechanism. Thereby, the light from the light source reflects off the reflector, and illuminates the reflective liquid crystal display panel brightly.

According to a second aspect of the present invention, in the liquid crystal lighting device according to the first aspect, the reflecting plate is movable from the illumination mechanism housing space to a position protruding from the display surface of the casing. It is composed of a plate and a second reflector for reflecting light from a light source stored in the illumination mechanism storage space to the first reflector.

Here, the "first reflector" is formed, for example, in a concave shape. This makes it possible to reliably guide the light reflected by the reflector with a small light reflection area to the entire surface of the reflection type liquid crystal display panel.

According to the second aspect of the invention, when the reflective liquid crystal panel can be illuminated, the light from the light source is reflected by the second reflector and the first reflector in order, and the liquid crystal display is displayed. Light up the panel brightly.

According to a third aspect of the present invention, in the liquid crystal display device according to the second aspect, the second reflector is provided with:
It is freely displaceable between an illumination position for guiding light from the light source in the direction of the display surface of the casing and a storage position for reducing the space occupied in the illumination mechanism storage space, and the displacement mechanism includes a first reflection plate and a second reflection plate. And displaced from the storage position to the illumination position in conjunction with the reflection plate.

Therefore, both the second reflector and the first reflector are displaced between the storage position and the illumination position by the operation of the displacement mechanism. This makes it easy to reduce the area occupied by the second reflector in the illumination mechanism storage space in the state where the second reflector is located at the storage position. The liquid crystal display panel can be used in a more compact state.

According to a fourth aspect of the present invention, there is provided the liquid crystal display device according to any one of the first to third aspects, further comprising a shutter member for opening and closing the illumination mechanism housing space.

Therefore, the illumination mechanism housing space is not exposed to the outside, and the illumination mechanism is protected.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an overall plan view, FIG.
FIG. 3 is a longitudinal side view of the same, and FIG. 3 is an overall longitudinal side view showing a state of illuminating the reflective liquid crystal display panel.

First, a flat casing-like casing 1 having an open surface is provided, and a reflective liquid crystal display panel 2 is attached to a display surface DS which is an open surface of the casing 1. This reflective liquid crystal display panel 2 has basically the same structure as that illustrated in FIG. Therefore, the description is omitted.

The interior of the casing 1 is divided into an electric component storage space 3 and a lighting mechanism storage space 4. The electrical component storage space 3 is formed at a position facing the back surface of the reflective liquid crystal display panel 2, and the illumination mechanism storage space 4 is formed at a position closer to one side inside the casing 1. In the electric component storage space 3, electric components (not shown) such as a power supply unit and a drive control circuit are stored and held.

A light source 5 is provided in the illumination mechanism housing space 4. As the light source 5, a straight-tube cold-cathode fluorescent lamp is used. The portion covering the light source 5 has a concave shape directed toward one side of the casing 1, and the concave wall surface having the concave shape serves as a light reflecting surface 6. The light reflecting surface 6 is easily formed by a well-known method of forming the casing 1 itself from a material having excellent light reflecting characteristics or coating the light reflecting material.

The concave surface of the light reflecting surface 6 is openably and closably closed by a second reflecting plate 7 having a mirror structure which constitutes a part of the reflecting plate. That is, the second reflecting plate 7 is hinged to the bottom of the casing 1 and the light reflecting surface 6
A1 (see FIG. 2) and the storage position A1
To an illumination position A2 (see FIG. 3) rotated by 45 degrees from the position. At the illumination position A2, the second reflecting plate 7 deflects the light from the light source 5 in a direction traveling from the display surface DS of the casing 1 to the outside.

Next, a first reflector 8 having a mirror configuration and constituting another part of the reflector is housed and held in the illumination mechanism housing space 4. The first reflecting plate 8 has a structure in which light emitted from the light source 5 and reflected by the second reflecting plate 7 is reflected on the curved inner surface, and is stored at the storage position B1 stored in the illumination mechanism storage space 4. (See FIG. 2) and an illumination position B2 that pops up from the housing position B1 to the outside of the casing 1 is freely displaceable.

Here, the display surface DS of the casing 1 includes:
As shown in FIG. 1, a knurling dial 9 that rotates around the axis of the light source 5 in common with the light source 5 is attached. The rotation axis of the second reflection plate 7 is connected to the rotation axis of the knurl dial 9 via a reduction gear train (not shown). Therefore, when the knurl dial 9 rotates, the second reflection plate 7 rotates between the storage position A1 and the illumination position A2. Also, the first reflector 8
Is connected to the rotating shaft of the knurled dial 9 via an operation direction changing mechanism (not shown) including a rack and pinion mechanism. Therefore, when the knurl dial 9 rotates, the first reflecting plate 8 is displaced between the storage position B1 and the illumination position B2. When the second reflector 7 and the first reflector 8 are displaced as described above, the second reflector 7 and the first reflector 8 operate so as not to interfere with each other. Here, a displacement mechanism (not shown) is configured.

Further, a shutter member 10 for opening and closing the illumination mechanism housing space 4 is hingedly connected to one end of the casing 1. The shutter member 10 is located in the same plane as the display surface DS of the casing 1 when closed. The shutter member 10 is normally urged in the opening direction by an urging member (not shown), and is positioned at a closed position by a stopper (not shown) that advances and retreats to a position that interferes with the movement trajectory. In FIG. 1, a knob 11 disposed near the knurl dial 9 on the side surface of the casing 1 has a structure in which the stopper moves forward and backward along the movement locus of the shutter member 10 by sliding.

In such a configuration, predetermined items are displayed on the reflective liquid crystal display panel 2 under the control of a drive control circuit (not shown). In this case, in a bright environment with a large amount of light such as outdoors during the daytime, the liquid crystal lighting device is used in a compact state with the second reflector 7 and the first reflector 8 stored in the storage positions A1 and B1. I do. On the other hand, in a dark environment where the amount of light is small, such as a dark indoor or an outdoor at night, the knurl dial 9 is turned to illuminate the second reflector 7 and the first reflector 8 by a displacement mechanism (not shown). It is displaced to positions A2 and B2. Thereby, the light source 5
Is reflected by the second reflector 7 and the first reflector 8 to illuminate the reflective liquid crystal display panel 2 brightly. This makes it possible to illuminate the liquid crystal display surface brightly even in an environment with a small amount of light and improve the visibility thereof, while taking advantage of the characteristics of the reflective liquid crystal display panel 2 that is small and lightweight. Further, both the second reflector 7 and the first reflector 8 are displaced to the storage positions A1, B1 and the illumination positions A2, B2. Accordingly, when the second reflector 7 is located at the storage position A1, the area occupied by the second reflector 7 in the illumination mechanism storage space 4 can be easily reduced, and a bright environment with a large amount of light can be easily achieved. Below, the reflection type liquid crystal display panel 2
Can be used in a more compact state.

Further, the shutter member 10 opens and closes the illumination mechanism housing space 4. Thereby, the lighting mechanism storage space 4
Is not exposed to the outside, and the illumination mechanism is protected.

[0029]

According to the first aspect of the present invention, the reflection type liquid crystal display panel is illuminated by popping up the first reflection plate which is a part of the illumination mechanism accommodated in the illumination mechanism accommodating space in the casing as required. Thus, the reflective liquid crystal display panel can be used in a compact state in a bright environment with a large amount of light, and can be brightly illuminated in a dark environment with a small amount of light.

According to a second aspect of the present invention, the reflector is separated into a first reflector and a second reflector, and the first reflector is popped up to illuminate the reflective liquid crystal display panel. Therefore, the angle of incidence of light on the reflective liquid crystal display panel and the layout of each part can be designed more freely, and therefore, the reflective liquid crystal display panel can be more efficiently illuminated with a more space-efficient arrangement. .

According to a third aspect of the present invention, the second reflector is also displaceable between the storage position and the illumination position so as to be displaced between the storage position and the illumination position in conjunction with the first reflection plate by a displacement mechanism. As a result, the second reflector can be held in the storage position so that the area occupied by the illumination mechanism storage space is further reduced, and the reflection type liquid crystal display panel is more compact in a bright environment with a large amount of light. Can be used.

According to the fourth aspect of the present invention, since the shutter member for opening and closing the lighting mechanism housing space is provided, it is possible to prevent the lighting mechanism housing space from being exposed to the outside, and thus to protect the lighting mechanism. be able to.

[Brief description of the drawings]

FIG. 1 is an overall plan view showing an embodiment of the present invention.

FIG. 2 is an overall vertical side view.

FIG. 3 is an overall vertical side view showing a state in which a reflective liquid crystal display panel is illuminated.

FIG. 4 is a schematic side view showing a backlight device of a liquid crystal display panel using a light guide plate.

FIG. 5 is a schematic diagram showing a structure of a reflection type liquid crystal display panel.

[Explanation of symbols]

 1: Casing 2: Reflective liquid crystal display panel 4: Lighting mechanism storage space 5: Light source 7: Reflector, second reflector 8: Reflector, first reflector 10: Shutter member A1, B1: Storage position A2 , B2: Lighting position

Claims (4)

[Claims] 1. A flat casing-shaped casing; a reflective liquid crystal display panel attached to one display surface of the casing; an illumination mechanism storage space provided on one side inside the casing; A light source housed in a mechanism housing space; and a light source configured to be movable from the lighting mechanism housing space to a lighting position protruding from the display surface of the casing, and in the lighting device, light from the light source is transmitted to the reflective liquid crystal display panel. And a displacement mechanism for displacing the reflector between its storage position and the illumination position. 2. The lighting device according to claim 1, wherein the reflecting plate includes a first reflecting plate movable from the lighting mechanism housing space to a position protruding from the display surface of the casing, and the light source housed in the lighting mechanism housing space. 2. The liquid crystal lighting device according to claim 1, further comprising: a second reflector that reflects the light to the first reflector. 3. The lighting device according to claim 1, wherein the second reflector is arranged between an illumination position for guiding light from the light source toward the display surface of the casing and a storage position for reducing an occupied space in the illumination mechanism storage space. 3. The liquid crystal lighting device according to claim 2, wherein the liquid crystal lighting device is displaceable, and the displacement mechanism displaces the first reflecting plate and the second reflecting plate from the storage position to the illumination position in conjunction with each other. 4. The liquid crystal lighting device according to claim 1, further comprising a shutter member that opens and closes the lighting mechanism storage space.